The present invention relates generally to nails having an expansion region.
More particularly, it relates to a nail which has an expansion region formed at a distance from a front end face of the nail and having two bowed expansible arms with a free space therebetween.
Nails of the above mentioned general type are known in the art. The German reference DE 33 45 331 A1 discloses a fixing element formed as a nail with an expansion region in the area of its front end face wherein the expansion region is formed by two outwardly bowed arms extending at a distance from one another. For anchoring of such a fixing element the shank of the fixing element is driven into a pre-drilled hole in masonry or similar material. When the shank is driven into the drilled hole, the expansible arms are compressed inwards by the wall of the drilled hole. An increased pressure by the expansible arms against the wall of the drilled hole can be achieved by an insert located between the expansible arms. After the driving-in operation, the expansible arms of the fixing element are pressed by the plastic and/or resilient restoring force of the insert against the wall of the drilled hole. As a result a correspondingly high holding force is achieved. However, because of the insert the resistance of the known nail to being driven in is very high.